Sheet conveyance problem release mechanism and sheet stacking apparatus

Abstract

A sheet conveyance release mechanism has a movable guide unit and a fixed guide unit adjacent to the movable guide unit. The mechanism has a horizontal conveyance guide unit for conveying a sheet in a substantially horizontal direction, and a vertical conveyance guide unit for conveying a sheet in a substantially vertical direction. A jam release lever moves the movable guide unit from a first position adjacent to the fixed guide unit in the horizontal direction to a second position below the fixed guide unit, and moves the vertical conveyance guide unit so as to separate from a guide surface.

1. A sheet conveyance release mechanism, comprising:
 a horizontal conveyance guide unit having a movable guide unit, and a fixed guide unit disposed adjacent to the movable guide unit, for conveying a sheet in a substantially horizontal direction; 
 a vertical conveyance guide unit for conveying the sheet in a substantially vertical direction; 
 a conveyance guide movement unit for moving the movable guide unit from a first position adjacent to the fixed guide unit in a horizontal direction, to a second position either under or over the fixed guide unit to overlap with the fixed guide unit, and separating the vertical conveyance guide unit from a guide surface facing the vertical conveyance guide unit, 
 a flapper for switching a conveyance path of the sheet conveyed between the horizontal conveyance guide unit and the vertical conveyance guide unit, and 
 a link member for rotating the flapper in an upward direction, wherein the link member includes a predetermined gear and is pivotally supported such that said predetermined gear is capable of separating from an opposingly arranged and meshed gear of a plurality of gears for transmitting drive force to convey the sheet. 
 
   
   
     2. The sheet conveyance release mechanism according to  claim 1 , wherein the predetermined gear is a part of a drive transmission path leading to a sheet discharge unit for discharging the sheet from an apparatus, and is disposed at an upstream side of the drive transmission path from a gear that directly applies drive force to the sheet discharge unit so that the predetermined gear is arranged to separate from the drive transmission path via the link member to interrupt drive transmission thereafter at an upstream side of the drive transmission path. 
   
   
     3. The sheet conveyance release mechanism according to  claim 1 , wherein the conveyance guide movement unit has a rotatable lever member connected to one of the movable guide unit and the vertical conveyance guide unit, and the flapper has a rotating shaft,
 the lever member rotates the movable guide unit to below the fixed guide unit such that the vertical conveyance guide unit is positioned in an oblique orientation, 
 a portion of the lever member engages the link member thereby moving the link member and separating the predetermined gear from the opposingly arranged gear to interrupt drive transmission, and 
 the link member rotates the flapper rotating shaft to rotate the flapper in an upward direction. 
 
   
   
     4. The sheet stacking apparatus comprising:
 at least one discharge tray for stacking a sheet discharged from a sheet discharge outlet; 
 a horizontal conveyance guide having a movable guide unit, and a fixed guide unit disposed adjacent to the movable guide unit, formed in a sheet conveyance path, for conveying the sheet in a substantially horizontal direction; 
 a vertical conveyance guide unit for conveying the sheet in a substantially vertical direction; 
 a flapper for switching the sheet conveyance path conveyed between the horizontal conveyance path and the vertical conveyance path, the flapper having a rotating shaft and being capable of rotating around the rotating shaft; 
 a conveyance guide movement unit for moving the movable guide unit from a first position adjacent to the fixed guide unit in a horizontal direction, to a second position under the fixed guide unit to overlap with the fixed guide unit, and separating the vertical conveyance guide unit from a guide surface facing the vertical conveyance guide unit; 
 a link member for rotating the flapper rotating shaft so as to rotate the flapper in an upward direction; and 
 a drive transmission unit having a plurality of gears for transmitting drive force for conveying and discharging the sheet to the discharge tray, 
 wherein the link member pivotably supports a predetermined gear capable of separating from an opposingly arranged and meshed gear of the plurality of gears. 
 
   
   
     5. The sheet stacking apparatus according to  claim 4 , wherein a plurality of discharge trays is arranged in the vertical orientation. 
   
   
     6. The sheet stacking apparatus according to  claim 4 , wherein the movable guide unit and the vertical conveyance guide unit are structurally integral and provide the guide surface for conveying a sheet. 
   
   
     7. A sheet stacking apparatus according to  claim 4 , further comprising a discharge roller disposed at the sheet discharge outlet for discharging the sheet to the discharge tray,
 wherein the drive transmission unit transmits the drive force to the discharge roller, and the predetermined gear is disposed at an upstream side of the drive transmission unit from a gear that directly applies the drive force to the discharge roller so that the predetermined gear is arranged to separate from a drive transmission path via the link member to interrupt the drive transmission thereafter at an upstream side of the drive transmission unit. 
 
   
   
     8. The sheet stacking apparatus according to  claim 4 , wherein the conveyance guide movement unit has a rotatable lever member connected to one of the movable guide unit and the vertical conveyance guide unit, and the flapper has a rotating shaft,
 the lever member rotates the movable guide unit to below the fixed guide unit such that the vertical conveyance guide unit is positioned in an oblique orientation, 
 a portion of the lever member engages the link member thereby moving the link member and separating the predetermined gear from the opposingly arranged gear to interrupt drive transmission, and 
 the link member rotates the flapper rotating shaft to rotate the flapper in an upward direction.